I have a question:

is the whammy bar bad for my guitar? bridge, strings, headstock...?

I noticed that it goes out of tune when I use it. Is there any way of avoiding that?

Thanks a lot
It's not bad for it. If it's a really cheap unit you can damage the posts by cranking on it too much, but that's fairly rare.
Using a string locking technique when stringing (google it) helps a lot, and keeping the nut lubricated is good. Sometimes having the screws too tight or loose on the trem mounting, or having the springs or claw poorly adjusted, will also cause issues. I'd google guides to setting up your particular trem and follow that for a start.
can i put a locking trem on every guitar? I have a jackson guitar, not the cheapest but not the best as well. kind of mid range
Do they make Jacksons that don't have a floyd as the trem?
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